1. Technical Field
This invention relates to a non-caloric fatty substitute to be used in the production of low calorie foods. More in particular, this invention relates to a novel composition comprising two multibasic acids, e.g. citric acid, connected by an ether linkage. Esterified to the carboxyl groups of the multibasic acid moieties are alcohols. The compositions are thus deemed ether bridged polyesters.
2. Background Information
Low calorie food products have become more popular with the public becoming more aware of the role which nutrition plays in weight maintenance. This is in part due to the fact that a lot of people have a sedentary lifestyle with little or no opportunity to exercise. This increasing awareness has been accompanied by a proliferation of diet schemes which enable the dieter to alter the types of food ingested rather than reduce the amount ingested. The production of low calorie food products has increased to provide such diet schemes with reasonable low calorie food products which are pleasing to the taste and therefore more apt to keep the dieter on a diet.
Recently, research in lipid metabolism and cancer has implicated certain saturated lipids as possible carcinogens. The literature recommends the lowering of fats within the diet as a possible prophylaxis against cancer. Accordingly, the food industry has responded to the demand for lower fat foods by providing fat substitutes which physically act as fats in the production of food products yet are not metabolized as readily as typical fats or are not metabolized at all. In accordance with the need for low calorie food products, such low fat substitutes are preferably low in caloric content.
U.S. Pat. No. 4,508,746 to Hamm discloses low calorie edible oil substitutes. Typically, a fat consists of a glycerol molecule having esterified thereto three fatty acids. Hamm discloses a reverse structure wherein a tri-carboxylic acid has esterified thereto long chain alcohols. The low calorie material is said to resist enzyme hydrolysis within the gut and that it is believed the composition cannot be assimilated in the human digestive tract. Citric acid is specifically taught away from in column 5, lines 39-44, because it is known to be unsuitable for most usages unless the free hydroxyl group of the citric acid moiety is protected by a suitable blocking group. It is respectfully submitted that those ordinarily skilled in the art consider blocking groups to be such materials as methyl, ethyl, phenyl or amino radicals. Another citric acid molecule is not suggested nor implied as being a possible "blocking group".
U.S. Pat. No. 4,247,568 to Carrington et al. discloses a low calorie food additive produced by heating starch with a tri-basic carboxylic acid, for example, citric acid, to produce a nondigestible product. The products are said to be useful for replacing wholly or in part the carbohydrates and/or fat content of foods thereby providing dietetic foods of low calorie content.
U.S. Pat. No. 3,600,186 to Mattson et al. discloses an example of a low calorie fat material which is less digestible than ordinary fats. The fat material is structurally a sugar fatty acid ester or sugar alcohol fatty acid wherein the sugar sorbitol is reacted with a fatty acid such as oleic acid to yield a sorbitol octaoleate. Other sugars, for example sucrose, are also reacted with fatty acids to yield sucrose polyesters.
U.S. Pat. No. 3,579,548 to Whyte et al. discloses a less digestible triglyceride fat. The material consists of a glycerol ester wherein alpha-branched carboxylic acids are esterified to the glycerol moiety.
U.S. Pat. No. 2,485,639 to Vahlteich et al. discloses incorporating tri-alkyl citrates into a glyceridic oil. The material is said to provide a shortening for improved baked goods.
U.S. Pat. No. 3,227,559 to Radlov discloses reacting citric acid with fatty acid glyceride to produce additives for baked products. The fatty acid glyceride utilized are the mono and diglyceride.
"Food Emulsifiers: Surface Activity, Edibility, Manufacture, Composition and Application", Lauridsen, J. AM OIL CHEMISTS' SOC., Vol. 53, 400-407, June 1976, contains a discussion concerning food emulsifiers, for example, citric acid ester of glycerol monostearate. The material is said to be used as an emulsifier for sausages and as an anti-spattering agent for margarine.
U.S. Pat. No. 3,042,530 to Kidger discloses shortening emulsifier and method for preparing the same. A reaction product is said to be derived by reacting citric acid, propylene glycol and mono-glyceride. The product is said to be useful as a shortening agent.
Citric acid is a versatile chemical, finding utility in many fields. Thus, many derivatives are known. For example, U. S. Pat. No. 3,239,555 to Miksch et al. discloses bis-citric acid ester. The free hydroxyl groups of two molecules of citric acid are esterified by a di-carboxylic acid. The esters are used as plasticizer.
Another example of a citric acid derivative is disclosed in U.S. Pat. No. 3,278,593 to Touey et al. Polyoxyalkylene ethers of citric acid are disclosed as metal deactivators.
There is a need in the art for new non-caloric and essentially non-digestible fat substitutes which can function as typical fats yet not be assimilated within the gut.
Accordingly, it is an object of the invention to provide a non-caloric, non-digestible fat substitute for use in low caloric and low digestible food products.
It is another object of the invention to provide a new fat substitute made from multibasic acids, wherein two multibasic acid molecules are joined by an ether or a multi-ether linkage, and wherein long chain alcohols are esterified to the citric acid carboxyls.
It is another object of the invention to provide a new fat substitute having increased hydrophobicity.
It is still another object of the invention to provide an ether fat substitute having greater stability against metabolism than the presently known ester linkages.
It is another object of the invention to provide a fat substitute having similarity to triglycerides in such characteristics as space filling models.
It is another object of the invention to provide a novel lubricant capable of lubricating machinery which handles food and machinery used to machine metals.
These and other further objects and features of the invention are apparent in the foregoing and ongoing specification which includes the claims.